Capturing Rainwater from Rooftops

An Efficient Water Resource Management Strategy that Increases Supply and Reduces Pollution

Many communities in the United States face serious threats to a safe, steady supply of water. These include a longstanding reliance on centralized water delivery systems that results in urban areas and agencies largely overlooking opportunities to integrate alternate local sources of water to meet their water supply needs; the unnecessary use of potable water for non-potable uses, such as outdoor landscape irrigation and indoor toilet flushing; climate change; and continually increasing areas of impervious surfaces in our landscape that result in stormwater runoff carrying pollution to our rivers, lakes, and beaches. Although the problems of water supply and water pollution can be complex, practical solutions for both are available now, such as capturing and using rainwater from rooftops.

Rooftop rainwater capture is a simple, cost-effective approach for supplying water that promotes sustainable water management. By using rainwater rather than allowing it to run off of paved surfaces to pick up pollutants and carry them to nearby surface waters. The practice provides numerous benefits:

Inexpensive, on-site supply of water that can be used for outdoor non-potable uses with little, if any, treatment, or for a variety of additional uses including potable supply with appropriately higher levels of treatment

Reduced (or no) energy and economic costs associated with treating and delivering potable water to end users because capture systems often use low-volume, non-pressurized, gravity fed systems or require only the use of a low power pump for supply

Reduced strain on existing water supply sources

Reduced runoff that would otherwise contribute to stormwater flows, a leading cause of surface water pollution and urban flooding